How do you reheat leftover prime rib without overcooking it?

Made a gloriously medium rare roast last night, have a big chunk leftover. Want to reheat for dinner, but not turn it into a well-done brick. What can I do to bring it back to life for a second go-around?

That is always tricky! We have had some luck by boiling some low sodium beef broth, then take it off the heat, and place the leftover roast in the pan, cover and wait 3-5 minutes to warm. Would rather eat it Luke warm than overdone. Usually I prefer to slice leftovers very thinly and eat cold with horseradish cream.

I'm with the cold sliced on a sandwich faction. What do you really need? White bread, prepared horseradish or horseradish sauce, mayonanaise iceberg lettuce, maybe some gherkins on the side. Often less is more.